diff --git a/modal_forms.admin.inc b/modal_forms.admin.inc
index 9173f3a..ff46aef 100644
--- a/modal_forms.admin.inc
+++ b/modal_forms.admin.inc
@@ -74,10 +74,10 @@ function modal_forms_admin_settings() {
     '#description' => t('Automatically activate Modal forms for links to contact.'),
   );
 
-  // Advanced settings.
+  // Page activation/deactivation settings.
   $form['modal_forms_advanced_settings'] = array(
     '#type' => 'fieldset',
-    '#title' => t('Advanced settings'),
+    '#title' => t('Page activation settings'),
     '#collapsible' => TRUE,
     '#collapsed' => TRUE,
   );
@@ -88,5 +88,130 @@ function modal_forms_admin_settings() {
     '#description' => t("Enter one page per line as Drupal paths. The '*' character is a wildcard. Example paths are %blog for the blog page and %blog-wildcard for every personal blog. %front is the front page.", array('%blog' => 'blog', '%blog-wildcard' => 'blog/*', '%front' => '<front>')),
   );
 
+  // Advanced modal settings.
+  $form['modal_forms_advanced_modal_settings'] = array(
+      '#type' => 'fieldset',
+      '#title' => t('Advanced modal settings'),
+      '#collapsible' => TRUE,
+      '#collapsed' => TRUE,
+  );
+  $form['modal_forms_advanced_modal_settings']['modal_forms_background_color'] = array(
+      '#type' => 'textfield',
+      '#title' => t('Background color'),
+      '#default_value' => variable_get('modal_forms_background_color', '#000'),
+      '#size' => 4,
+      '#maxlength' => 7,
+      '#required' => TRUE,
+      '#description' => t('The color of the background behind the modal. Should be entered in html hex notation (eg #000).'),
+  );
+  $form['modal_forms_advanced_modal_settings']['modal_forms_opacity'] = array(
+      '#type' => 'textfield',
+      '#title' => t('Background opacity'),
+      '#default_value' => variable_get('modal_forms_opacity', 0.85),
+      '#size' => 3,
+      '#maxlength' => 5,
+      '#required' => TRUE,
+      '#description' => t('The opacity of the background behind the modal. Should be entered as a decimal value (eg 0.85 = 85% opacity).'),
+  );
+
+  // Modal popup size settings
+  $modal_types = array('fixed' => t('Fixed'), 'scale' => t('Scale'));
+  $form['modal_forms_size_settings'] = array(
+    '#type' => 'fieldset',
+    '#title' => t('Modal popup sizes'),
+    '#collapsible' => TRUE,
+    '#collapsed' => TRUE,
+  );
+  // Popup Small
+  $form['modal_forms_size_settings']['modal_forms_popup_small'] = array(
+    '#type' => 'fieldset',
+    '#title' => t('Modal popup small'),
+    '#collapsible' => TRUE,
+    '#collapsed' => TRUE,
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_small']['modal_forms_popup_small_type'] = array(
+      '#type' => 'radios',
+      '#title' => t('Type'),
+      '#default_value' => variable_get('modal_forms_popup_small_type', 'fixed'),
+      '#options' => $modal_types,
+      '#description' => t('Fixed sizes should be entered in pixels. Scaled sizes should be entered as a decimal percentage of the screen region (eg 0.8 = 80% of screen width/height).'),
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_small']['modal_forms_popup_small_width'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Width'),
+    '#default_value' => variable_get('modal_forms_popup_small_width', 300),
+    '#size' => 3,
+    '#maxlength' => 5,
+    '#required' => TRUE,
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_small']['modal_forms_popup_small_height'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Height'),
+    '#default_value' => variable_get('modal_forms_popup_small_height', 300),
+    '#size' => 3,
+    '#maxlength' => 5,
+    '#required' => TRUE,
+  );
+  // Popup Medium
+  $form['modal_forms_size_settings']['modal_forms_popup_medium'] = array(
+    '#type' => 'fieldset',
+    '#title' => t('Modal popup medium'),
+    '#collapsible' => TRUE,
+    '#collapsed' => TRUE,
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_medium']['modal_forms_popup_medium_type'] = array(
+    '#type' => 'radios',
+    '#title' => t('Type'),
+    '#default_value' => variable_get('modal_forms_popup_medium_type', 'fixed'),
+    '#options' => $modal_types,
+    '#description' => t('Fixed sizes should be entered in pixels. Scaled sizes should be entered as a decimal percentage of the screen region (eg 0.8 = 80% of screen width/height).'),
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_medium']['modal_forms_popup_medium_width'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Width'),
+    '#default_value' => variable_get('modal_forms_popup_medium_width', 550),
+    '#size' => 3,
+    '#maxlength' => 5,
+    '#required' => TRUE,
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_medium']['modal_forms_popup_medium_height'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Height'),
+    '#default_value' => variable_get('modal_forms_popup_medium_height', 450),
+    '#size' => 3,
+    '#maxlength' => 5,
+    '#required' => TRUE,
+  );
+  // Popup Large
+  $form['modal_forms_size_settings']['modal_forms_popup_large'] = array(
+    '#type' => 'fieldset',
+    '#title' => t('Modal popup large'),
+    '#collapsible' => TRUE,
+    '#collapsed' => TRUE,
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_large']['modal_forms_popup_large_type'] = array(
+    '#type' => 'radios',
+    '#title' => t('Type'),
+    '#default_value' => variable_get('modal_forms_popup_large_type', 'scale'),
+    '#options' => $modal_types,
+    '#description' => t('Fixed sizes should be entered in pixels. Scaled sizes should be entered as a decimal percentage of the screen region (eg 0.8 = 80% of screen width/height).'),
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_large']['modal_forms_popup_large_width'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Width'),
+    '#default_value' => variable_get('modal_forms_popup_large_width', 0.8),
+    '#size' => 3,
+    '#maxlength' => 5,
+    '#required' => TRUE,
+  );
+  $form['modal_forms_size_settings']['modal_forms_popup_large']['modal_forms_popup_large_height'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Height'),
+    '#default_value' => variable_get('modal_forms_popup_large_height', 0.8),
+    '#size' => 3,
+    '#maxlength' => 5,
+    '#required' => TRUE,
+  );
+
   return system_settings_form($form);
 }
diff --git a/modal_forms.module b/modal_forms.module
index 3d31b54..4d37a2c 100644
--- a/modal_forms.module
+++ b/modal_forms.module
@@ -151,13 +151,13 @@ function _modal_forms_doheader() {
   $js_settings = array(
     'modal-popup-small' => array(
       'modalSize' => array(
-        'type' => 'fixed',
-        'width' => 300,
-        'height' => 300,
+        'type' => variable_get('modal_forms_popup_small_type', 'fixed'),
+        'width' => floatval(variable_get('modal_forms_popup_small_width', 300)),
+        'height' => floatval(variable_get('modal_forms_popup_small_height', 300)),
       ),
       'modalOptions' => array(
-        'opacity' => 0.85,
-        'background' => '#000',
+        'opacity' => floatval(variable_get('modal_forms_opacity', 0.85)),
+        'background' => variable_get('modal_forms_background_color', '#000'),
       ),
       'animation' => 'fadeIn',
       'modalTheme' => 'ModalFormsPopup',
@@ -166,13 +166,13 @@ function _modal_forms_doheader() {
     ),
     'modal-popup-medium' => array(
       'modalSize' => array(
-        'type' => 'fixed',
-        'width' => 550,
-        'height' => 450,
+        'type' => variable_get('modal_forms_popup_medium_type', 'fixed'),
+        'width' => floatval(variable_get('modal_forms_popup_medium_width', 550)),
+        'height' => floatval(variable_get('modal_forms_popup_medium_height', 450)),
       ),
       'modalOptions' => array(
-        'opacity' => 0.85,
-        'background' => '#000',
+        'opacity' => floatval(variable_get('modal_forms_opacity', 0.85)),
+        'background' => variable_get('modal_forms_background_color', '#000'),
       ),
       'animation' => 'fadeIn',
       'modalTheme' => 'ModalFormsPopup',
@@ -181,13 +181,13 @@ function _modal_forms_doheader() {
     ),
     'modal-popup-large' => array(
       'modalSize' => array(
-        'type' => 'scale',
-        'width' => 0.8,
-        'height' => 0.8,
+        'type' => variable_get('modal_forms_popup_large_type', 'scale'),
+        'width' => floatval(variable_get('modal_forms_popup_large_width', 0.8)),
+        'height' => floatval(variable_get('modal_forms_popup_large_height', 0.8)),
       ),
       'modalOptions' => array(
-        'opacity' => 0.85,
-        'background' => '#000',
+        'opacity' => floatval(variable_get('modal_forms_opacity', 0.85)),
+        'background' => variable_get('modal_forms_background_color', '#000'),
       ),
       'animation' => 'fadeIn',
       'modalTheme' => 'ModalFormsPopup',